For many years underwater trenches have been needed for various applications. For instance, many examples can be given where undersea cable networks have been installed for communications purposes. Moreover, the need for such undersea cable networks will continue with even more urgency as new and improved cable networks with increased communications capabilities are developed to meet future communication needs.
A critical aspect of undersea trenching is the establishment of a suitable route. The selection of a proper route requires that obstacles, such as underwater mountain ranges and canyons, be avoided. In addition, it happens that the soil conditions encountered when excavating an underwater trench can be very important, even where canyons and mountain ranges are not encountered. For instance, the seabed, although flat, may comprise solid rock. On the other hand, the seabed may be extremely muddy and lack any real compaction. In cases where the seabed is largely rock, it may be impossible for the trenching equipment to properly excavate. Alternatively, in cases where the seafloor lacks adequate compaction, there may be inadequate support for the trenching equipment or the trench itself may collapse subsequent to the trenching operation.
In the past, information about sea floor soil conditions was generally obtained by collection of core samples. The collection of core samples involved repeatedly releasing and retrieving a coring penetrometer. The coring penetrometer would collect a sample of the seafloor at the point of impact and the sample would be analyzed after retrieval of the coring penetrometer. Unfortunately, the retrieval of the coring penetrometer and the subsequent analysis of the seafloor sample were time consuming procedures. In particular, the use of the coring penetrometer required that the release vessel loiter at each release point while the coring penetrometer was released and recaptured. As a result, the establishment of a suitable route for an undersea trench has generally been an arduous and expensive process.
In light of the above, it is an object of the present invention to provide a system and method for identifying a route for the excavation of an underwater trench which verifies whether a proposed route is appropriate, and which replots the proposed route as necessary. Another object of the present invention is to provide a system and method for identifying a route for the excavation of an underwater trench which continuously identifies penetrometer launch points along a proposed route according to data received at prior launch points. Still another object of the present invention is to provide a system and method for identifying a route for excavation of an underwater trench which minimizes the time spent at each penetrometer launch point. Still another object of the present invention is to provide a system and method for identifying a route for excavation of an underwater trench which provides for onboard analysis of data collected at a launch site, and which integrates data collected from multiple launch sites to establish an actual route for an underwater trench. Yet another object of the present invention is to provide a system and method for identifying a route for excavation of an underwater trench which is simple to use, easy to operate and comparatively cost effective.